M85.9 – Disorder of bone density and structure, unspecified

ICD-10-CM 2027 diagnosis code · Disorders of bone density and structure

Billable code

ICD-10-CM code M85.9

Code: M85.9 (claims format: M859)
Description: Disorder of bone density and structure, unspecified
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 13. Diseases of the musculoskeletal system and connective tissue (M00-M99)
Block: M80-M85 Disorders of bone density and structure
Parent codes: M85

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

M85 – Other disorders of bone density and structure

Excludes1 (not coded here):

osteogenesis imperfecta (Q78.0)
osteopetrosis (Q78.2)
osteopoikilosis (Q78.8)
polyostotic fibrous dysplasia (Q78.1)

Index terms for M85.9

Entries in the ICD-10-CM alphabetic index that lead to this code:

Disorder, bone, density and structure

Related codes in M85

M85.0 – Fibrous dysplasia (monostotic)Header
M85.1 – Skeletal fluorosisHeader
M85.2 – Hyperostosis of skullBillable
M85.3 – Osteitis condensansHeader
M85.4 – Solitary bone cystHeader
M85.5 – Aneurysmal bone cystHeader
M85.6 – Other cyst of boneHeader
M85.8 – Other specified disorders of bone density and structureHeader

Frequently asked questions

What is ICD-10 code M85.9?

M85.9 is the ICD-10-CM code for disorder of bone density and structure, unspecified, in the block M80-M85 (Disorders of bone density and structure).

Is M85.9 a billable code?

Yes. M85.9 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does M85.9 belong to?

It belongs to category M85 – Other disorders of bone density and structure.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.